If you're body isn't getting what it believes is enough to
run itself, sometimes it holds on to weight
! Have you tried looking into a program like Weight
Watchers, Jenny Craig, Curves, or the Biggest Looser Club (usually through work)? I don't know if you could eat some of the foods, depending on how strict of a food diet your particular sect follows. But they may be able to help point you in a direction.
Out of curiosity have your doctors tested your thyroid levels- your TSH, T4 and T3?